1. Field of the Invention
The present invention relates to stereoscopic photographing system. More specifically, the present invention relates to a photographing system and method for generating stereoscopic images of a full sphere surrounding a viewer 360 degrees both horizontally and vertically, or of a continuous part thereof, comprising a spherical array of lenses having non-parallel optical axes.
2. Discussion of the Related Art
Stereoscopic and panoramic photographing systems are known in the art. In conventional stereoscopic photographing, stereo pairs are taken by twin-cameras having parallel optical axes and a fixed distance between their aligned lenses. The pair of the obtained images can then be displayed by any of the known techniques for stereoscopic displaying and viewing. All of these techniques are based, in general, on the principle that the image taken by the right lens is displayed to the viewer's right eye and the image taken by the left lens is displayed to the viewer's left eye.
Panoramic photographing is conventionally done either by a very wide-angle lens, such as a “fish-eye” lens, or by “stitching” together slightly overlapping adjacent images to cover a wide, up to a fill circle, field of vision. Recently, the same techniques used for panoramic imaging are also exploited for obtaining spherical images. However, the panoramic or spherical images obtained by using said techniques are not stereoscopic, nor do they give to the viewer a perception of depth.
Moreover, the field of the so called “Virtual Reality” has gained high popularity in recent years. However, imaging systems for virtual reality, which are based on real images and not on computer generated (or other synthetically made) images, are still far from achieving images of a satisfactory quality. This is due mainly to the difficulties in obtaining real images that are full spherical as well as stereoscopic.
Accordingly, there is a need for an improved photographing system which will provide fully spherical, and fully stereoscopic real images.
The present invention is based on the finding that a stereoscopic image can be obtained by overlapping images taken by lenses having non-parallel optical axes, providing that said lenses' fields of view are overlapping to a great extent. This finding enables a full spherical stereoscopic photographing by a three dimensional array of cameras pointing out from a common center for covering the whole surroundings, both horizontally and vertically.